Dense Stereo Range Sensing with Marching Pseudo-Random Patterns

As an extension to classical structured lighting techniques, the use of bi-dimensional pseudo-random color codes is explored to perform range sensing with variable density from a stereo calibrated rig and a projector. Pseudo-random codes are used to create artificial textures on a scene which are extracted and grouped in a confidence map to ensure reliable feature matching between pairs of images taken from two cameras. Depth estimation is performed on corresponding points with progressive refinement as the pseudo-random pattern projection is marched over the scene to increase the density of matched features, and achieve dense 3D reconstruction. The potential of bi-dimensional pseudo-random color patterns for structured lighting is demonstrated in terms of patterns computation, ease of extraction, matching confidence level, as well as density of depth estimation for 3D reconstruction.